When the Royal Scottish National Orchestra was last in Shetland 20 years ago, they played concerts in Lerwick then headed back south. This time they settled in for a five-day outreach residency, and it's been, as this part of the world is wont to be, a total hoot. Players were teamed up with local musicians and dispatched to the remotest islands – out to Unst, northernmost tip of the UK, and even Foula, tiny and sheer-cliffed, with a population of 20, give or take.

Local fiddler Chris Stout was commissioned to write a piece for the occasion, and to include in it a tune that each team could arrange for a kind of inter-island playoff. Those versions had turned out brilliantly varied and imaginative; the full version, called Tingaholm after Shetland's ancient Norse gathering point, was premiered in Lerwick.

As always, Stout's tunes are haunting, underpinned with earthy drones and ferocious, foot-stomping rhythms. He treats his violins like a band of Shetland fiddlers hurtling through a lopsided fugue, and fragments his melodies into rhythmic motives with shifting accents à la Stravinsky. There's a touch of Reich, too, in his ostinatos that loop until fadeout. Some of these tripped the orchestra – probably a mix of the score needing fine-tuning and the orchestra being under-rehearsed. There's great material here, though; I'd love to hear a repeat performance before long.

Britten's Four Sea Interludes and Sibelius's First Symphony made up the rest of the programme. It's tricky to conjure much magic in school-gym acoustics, but the orchestra under David Danzmayr did what they could; really, though, the magic of this residency has been outside the formal concerts. Remote schools workshops, impromptu late-night sessions crammed with locals and orchestral players – the outreach, it seems, has been mutual.